Inkweed
Botanical Name
Phytolacca octandra
Family
Phytolaccaceae (inkweed)
Where is it originally from?
Tropical South and Central America
What does it look like?
Bushy, spreading, hairless, smelly, perennial subshrub (<2 m tall, more if supported) with a very deep, pliable taproot. Hollow and brittle stems are softly woody near base, usually reddish, much branched, with numerous white dots of crystalline calcium oxalate inside. Narrow-oval leaves (40-150 x 15-50 mm) are alternate and light green when young, but occasionally turn reddish in autumn. Dense, erect, cylindrical flower clusters (up to 7 cm long, Nov-Aug) turning from green to pink are produced along the main stem, followed by succulent, purple-black berries (8 mm in diameter) with dark red juice containing seeds.
Are there any similar species?
Pokeweed (Phytolacca americana and P. clavigera) is similar but has much bigger leaves and flowering/fruiting clusters.
Why is it weedy?
Grows and matures quickly, producing many well dispersed, long-lived seeds. Tolerates damage, wind, fire, all loose soils, and wet to moderately dry conditions, but is intolerant of deep shade, deep humus and heavy frost. Toxic, so stock avoid it.
How does it spread?
Birds, soil and occasionally water movement spread the berries containing the seeds. Seed sources include infested waste places, neglected crops, and disturbed, burnt or sprayed farm or conservation land.
What damage does it do?
Competes for space and nutrients in pioneer plant communities, and can temporarily inhibit the establishment of seedlings of native plant species. Normally followed by native species, but can also be followed by vines or other weeds.
Which habitats is it likely to invade?
Heavily disturbed forest and shrubland, short tussockland, bare land, cliffs, coastline inshore and offshore islands, and riverbeds.
What can I do to get rid of it?
Control this weed only where it is rare, habitat is vulnerable, or where disturbance has caused dense sites. Regenerating shady sites (or where groundcover is becoming dense) can normally be left as the weed will be crowded out.
1. Pull out small plants: Leave on site to rot down, minimise disturbance.
2. Slash stems close to ground. Leave on site to rot down.
3. Cut down and paint stump (all year round): metsulfuron-methyl 600g/kg (1g/L).
CAUTION: When using any herbicide or pesticide, PLEASE READ THE LABEL THOROUGHLY to ensure that all instructions and directions for the purchase, use and storage of the product, are followed and adhered to.
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